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Background: The authors compared the efficacy of the different approaches to saphenous nerve block.

Methods: The following approaches to saphenous nerve block were compared in 10 volunteers: perifemoral, transsartorial, block at the medial femoral condyle, below-the-knee field block, and blockade at the level of the medial malleolus. Each volunteer underwent all five blocks, and the interval between blocks was 3-7 days. The sequence of injection was randomized by Latin square design. Sensory blockade at the medial aspects of the leg and foot and the strength of the anterior thigh muscles were noted.

Results: The transsartorial, perifemoral, and below-the-knee field block approaches were more effective than block at the medial femoral condyle in providing sensory anesthesia to the medial aspect of the leg. The transsartorial approach was more effective than block at the medial femoral condyle and below-the-knee field block in providing sensory anesthesia to the medial aspect of the foot. Compared with the perifemoral approach, the transsartorial approach did not cause weakness of the hip flexors and the knee extensors. In volunteers with partial numbness in the medial aspect of the foot, supplemental block of the medial dorsal cutaneous branch of the superficial peroneal nerve resulted in complete sensory blockade.  相似文献   

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The goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc.  相似文献   
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An unusual association of diencephalic syndrome of emaciation, pituitary insufficiency for 2 years and suprasellar craniopharyngioma is described in a 45-year-old male. The tumour was found to be adherent to the anterior hypothalamic structures. Following partial excision, irradiation and hormonal replacement he regained his appetite, subcutaneous fat and body weight gradually.  相似文献   
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Effect of Endoscopic Sphincterotomy on Gallbladder Motility   总被引:2,自引:0,他引:2  
In experimental animals, sphincterotomyfacilitates passage of solids from the gallbladder andinhibits gallstone formation apparently by improvementin gallbladder emptying. In humans, however, gallbladder emptying has not been studied followingendoscopic sphincterotomy (ES) in patients withgallstones. We therefore prospectively studied restingand cerulinstimulated gallbladder volumes by real timeultrasonography in 15 patients of choledocholithiasis withgallbladder in situ (eight with and seven withoutgallbladder calculi) before and after (after bile ductclearance) ES. ES significantly lowered restinggallbladder volume (21.2 ± 10.6 vs 11.1 ±5.0; P < 0.0001) and cerulin-stimulated residualgallbladder volume (10.8 ± 5.6 vs 4.4 ±2.1; P < 0.0001). ES also significantly increased thegallbladder ejection fraction (47.3 ± 12.1% vs 58.8 ± 11.1%; P < 0.0001). Therate constant for gallbladder emptying after cerulininfusion also increased significantly after ES(–0.022/min vs –0.031/ min; P < 0.0001).Significant improvement in gallbladder motility was observed in both groups ofpatients with and without gallbladder calculi. ESsignificantly improves gallbladder motility inhumans.  相似文献   
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The optimal conditions for inactivation of Bordetella pertussis organisms with glutaraldehyde for the production of a safe and potent whole cell pertussis vaccine were investigated. Two bacterial harvests from B. pertussis strain 10536 were treated with glutaraldehyde, each with 0.025, 0.05 and 0.1% concentrations of glutaraldehyde for 10, 60 and 120 min. The nine types of glutaraldehyde-inactivated pertussis vaccine (GIPV) and conventional heat-inactivated pertussis vaccine (HIPV) preparations made from two bacterial harvests were comparatively evaluated for the mouse weight gain test (MWGT), potency, and the histamine-sensitization (HS) and leucocytosis-promoting-factor (LPF) tests. The minimum period for killing the B. pertussis organisms with glutaraldehyde was>10 min for 0.025%, 10 min for 0.05% and 5 min for 0.1% concentration. The average loss in opacity varied from 5 to 10% for GIPV preparations and was 14% for HIPV preparations. The GIPV preparations except those inactivated with 0.025% glutaraldehyde for 10 min (GIPV-A) were much less toxic than the HIPV preparations in the MWGT. The GIPV-A preparations did not pass the MWGT. The GIPV preparations were also much less toxic in HS and LPF tests than the HIPV preparation. The potency of GIPV preparations inactivated with 0.05% glutaraldehyde for 10 min (GIPV-D) was similar to that of HIPV preparations. The prolonged treatments with glutaraldehyde reduced the potency. The GIPV-D preparation with good potency and less toxicity was found to be inactivated with glutaraldehyde under optimal conditions. All the preparations were innocuous in the abnormal toxicity test.  相似文献   
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